The parameters dictionary contains a null entry for parameter 'customItemId' of non-nullable type 'System.Int32' for method 'System.Threading.Tasks.Task`1[System.Web.Mvc.ActionResult] DownloadProof(Int32, Boolean, Boolean)' in 'CustomFuzeWeb.Controllers.HomeController'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter. Parameter name: parameters